The embodiments of the present invention relate to wireless communications, and more particularly, to a wireless local area network (WLAN) apparatus which is capable of dynamically adjusting the operating frequencies of a wireless device and a wireless device, to thereby improve the performance of a wireless communications system.
Wireless local area networks (WLANs) are widely applied in various specifications, such as IEEE 802.11a, IEEE 802.11b, IEEE 802.11g, IEEE 802.11n, and IEEE 802.11ac. Some of these standards employ a multiple input multiple output (MIMO) OFDM scheme, and may support both the 2.4 GHz and 5 GHz bands.
FIG. 1 is a diagram illustrating exemplary continuous spectrums 101 and non-continuous spectrums 102 to be setup in its network. The bandwidth of the continuous spectrums 101 may be 20 MHz, 40 MHz, 80 MHz, or 160 MHz; and the selected bandwidth of the non-continuous spectrums 302 may be any of the following combinations of primary and secondary segments: 40 MHz+40 MHz, 40 MHz+80 MHz, 80 MHz+40 MHz, and 80 MHz+80 MHz. When receiving one non-continuous combination, two receiving circuits are required for receiving the primary segment and the secondary segment, respectively.
The receiving schemes of the existing wireless transceivers are not flexible. For example, when only first segment signals are transmitted, the receiving circuit arranged for receiving the second segment signals will enter an idle mode, so the entire system is not fully used. There is therefore a need for an innovative transmitter and receiver design to solve the aforementioned problem.